Will these fit my 2002 toyota 4 runner sr5?

It should as they're a universal fit. They fit on both my jeep compass and my H3 Hummer so they do fit a pretty wide range of seat sizes. Hope this helps. They are good product!

will it fit on 2015 Toyota Camry SE?

Yes there made to fit any car. It will stretch to fit.

will this fit a 98 Buick parkavenue ultra?

Yes, this item will fit.

Are these covers fast and easy to put on?

Yes, they are very easy to put on you just pull it over the whole back part of the seat like a pillow case. They are very well made and come with straps to fasten on the bottom. They even give you extra fasteners to use, but honestly I didn't even use the fasteners because there is no need. They stay on pretty tight and don't move. I am very satisfied with mine. Very well made.

Does it fit toyota Yaris

It should fit most seats. The seat covers are also side airbag friendly.